Electrolytic system



June 17, 1930. "J, W. SCOTT ELEGTROLYTIC; SYSTEM Filed Dec. 2s, 192s 15 these tanks.

Patented June- 17, "1930.

.UNITED STATES `PATENr OFFICE JAMES WALTER SCOTT, F CHICAGO, ILLINOIS, .ASSIGNOR TO WESTERN ELECTRIC COMPANY, INCORPORATEDZUF NEW YORK, N'. Y., A CORPORATION OF NEW`YORK ELECTROLYTIC SYSTEM Application iled December 23, 1926. Serial No. 156,588.

' This invention relates to electrolytic systems, and more particularly to electrolytic systems employed in connection with the recovery of metals. f

It is the practice in some process of recovering certain metals, such as copper, from an electrolytic solution, to circulate the electrolyte' .through a series of interconnected containers or tanks. If a-'dif- 10 ference in electrical potential exists between these interconnected tanks, there will necessarily be a certain amount of current How in the portion of the electrolytic solutionwhich passes thrQugh the couplingsinterconnecting Under such conditions electrolytic decomposition of the portion of the solution passing through the couplings takes place, which in some instances results in the i formation of a metallicv deposit which deleteriously ailects the operative effectiveness of theentire electrolytic system.

The primary object of this invention is to' provide a 'simple and-eiectivesystem of interconnected electrolyte retainers which obviates the aforementioned diiculty.

In accordance with the general'features of the invention one embodiment thereof comprises a plurality of pairs of electrolytetanks supplied with suitable anodes and cathodes connected in series with a source of electri- -cal current supply and designedl to decompose an electrolytio solution, as vfor example an aqueous solution of copper sulphate, within the tanks to recover copper therefrom.

35. Each pair of tanks is interconnected by a coupling which permits the passage therethrough of `thev electrolyte fremone tank to a-nother,and lwhich in itself constitutes an auxiliary eletrolytic cell as cathode and anode 49 electrodes electrically `connected to the respective interconnected cells .are providedA therein. A copper catho-de Within the auxiliary cell serves to recover copper from the solution passing through the cell, this cop- 45 per being liberated due to the current flow instances inthe of al type which are representative of one embodiment of the invention;

Fig. :Zis a vertical sectional View taken longitudinally of one of the tank couplings on the line 2-2 of Fig."1, and

Fig. 3 is a plan View .of the coupling disclosed in Fig. 2, the cover thereof being lroken away to disclose parts otherwise hid- Referring now to the drawing wherein like l numerals have been employed to designate .similar parts throughout the various figures,

it will be .observed that a series of elongate-cl tanks 10 and a series of similar companion tanks 11. in alignment therewith are provided with linings 13 of lead or other suitablematerial (Fig. 2.). These. lead linings 13 are enclosed Within suitable casings 14,

. and positioned Within each tank are a plurality of anode plates 16 and companion cathplates 17. 'The anode plates ltcomprise a sheet of lead or other suitable material, and the cathode plates 17 preferably comprise sheets of copper which extend downwardly into their respective tanks, these anode and cathode plates being supported atene extremity by andelectrically connected with copper bus bars 19, which are positioned adjacent to and extend longitudinally on the upper sides 'of each tank. As disclosed in Fig. 1, one of the copper bus bars 19 adjacent tol the foremost tank 10 is electrically connected through a switch 20 to one terminal of a suitable source of current supply, such as a. generator 22, and the opposite terminal of sai-d generator is connected with one of the bus bars positioned adjacent the foremost tank 11.- Therear companion tanks 10 and 11 are 'electrically connected byabus bar 23 which extends therebetween,-and thus itwill be clear that when an electrolyte 25, such as copper sulphate, is supplied tothe tanks and the switch 2O is closed the tanks will be connected in series, the current from the generator 22 flows from one terminal thereof in a direction indicated by arrows in Fig. 1, through lthe entire series of tanks and .then back to the opposite generator terminal,

lOO

able source of supply (not shown) through a lead pipe 26, which serves to direct the solution into each of the tanks at one extremity thereof. These tanks are connected at their opposite extremities' with the tanks 11 by means of an interconnector or coupling d enoted generally by the numeral 28, and it will be observed that the tanks 11 are positioned at a lower level than the tanks 10 to permit the free passage or overflow of' the electrolyte 25 from the tanks 10 into the tanks 11.- The electrolyte from the tanks 11 is returned through a pipe 29 to the original source of the electrolyte supply (not shown) and thus the continuous passage or circulation of the electrolyte through the tanks is effected. The continued circulation of the electrolyte through the tanks in the above described manner serves to more ellectively render possible a complete recovery of metallic copper from the electrolytic sulphate solution.

Each of the interconnectors or couplings 28 comprises a box-like conduit `31, preferably comprised of Wood or any other suitable nonconducting material, supported by a frame 32, and is provided with a removable cover 33. One end of each conduit 31 is connected with a companion tank 10 by means of a lead connect-or 35, while the opposite end of the conduit is provided with a depending portion 36 which opens downwardly into acompanion tank 11. The lead connector' 35 contacts at one extremity with the lead lining 13 of theI tank 10, and the opposite end of the connector contacts with a lead plate 38 positioned in the conduit 31. Traversing and resting uponthe y bottom portion of the conduit 31 at the end adjacent the tanks 1-1 is a copper rod 39 which extends through the wall of the conduit (Fig. 3) and is suitably connected asby means ol' a terminal post 41 with the lining 13 ofthe tank 11.

By reason of the fact that the tanks are electrically connected in series it will be obvious that the voltage impressed upon the electrolyte contained within the foremost tank 10- will be higher than the voltage impressed upon the electrolyte contained within its companion rear tank 11, and hence there will be a tendency for a current .to flow-trom the tank 10 to the tank 11 through the portion of the electrolyte passing through the coupling 28. By having the lead plate 38 within the conduit 31 electrically connected with the lining of the tank 10 through the connector 35, as described, this plate will serve as an auxiliary anode for the electrolyte flowing through the conduit. Likewise the copper rod 39 positioned at the extremity of the conduit 3 1 opposite from the plate 38 will serve as a cathode, "and hence electrolytic decomposition which will consequently take place within this portion of the electrolyte will cause metallic copper to be deposited upon the rod 39. By this construction it will be understood that the wooden conduit 31 andl thel above mentioned auxiliary anode and cathode which comprise the coupling 28 will constitute an auxiliary electrolytic cell, which will operate to localize the deposition of copper recovered from the solution passing therethrough.

Experience has shown that when conventional types of couplings are employed to connect electrolyte retainers, such as the tanks 10 and 11, without the provision of an auxiliary anode and cathode, electrolytic decomposition of the solution'passing through the coupling results in a deposition of metallic lining of the tanks 11. Under such conditions the lead lining as in the tank 10 serves as an anode and the lead lining as in the tank 11 serves as a cathode, and the copper is not deposited in a localized area such as upon the rod 39, as hereinbefore described, but the deposit thusV produced forms a spongy mass throughout the length of the coupling which not only presents an obstruction to the free flow of electrolyte from one tank to another as the size of the deposit increases but which also tends to decrease the electrical resistance between the tanks, and hence cause a correl orcoupling 28, deposition of copper from the electrolyte flowing between the tanks is positively controlled and the above mentioned deleterious effects are precluded. vlVhen the copper rod 39 is increased to a predetermined size as a result of the deposit of copper thereon it may easily be removed and replaced by another rod, and this convenient method of removing the deposited copper should be distinguished from the difliculty and inconvenience necessarily incident to the frequent removal of an accumulated mass of spongy copper deposit. In a process ot copper recovery from aA group of electrolyte tanks electrically connected in series as disclosed in Fig. 1, the greatest amount of copper recovery within the couplings 28 between each pair of tanks obviously takes place in the coupling between the two foremost tanks 1() and 11, because the largest difference in electrical potentials exists between the electrolytes in these tanks as distinguished from a 'considerably smaller difference in potential trolytic solution'between the tanks and positively `p'recluding the formation of any injurious metallic deposits throughout the elecbeen drawn to define modifications'l which invention.

What 1s clarmedisi come within the truespirit and scope of the 1. In a system fol-the electrolytic deposition ofmetals,aplurality of tanks for'contain- `lng` an electrolyte, 'theportionof the electrolyte in one tank being -maintained -at ahigher potential than the portion inthe other, means interconnecting the tanks to direct the pas# sage `of the electrolyte therebetween, and

means associate'd with the interconnecting means tocontrol electrolytic deposition' occasionedbythecurrent How in the portion of the electrolyte which passes through the interconnecting-means. a

2. In a coupling for systems forlthe electrolytic deposition of metals, an electrolyte conlduit, and means within the 'conduit lor con'- trollin electrolyt-ic de, ositionv within van electro yte passing theret ough. v

3. In a coupling for systems for the electro'- lyticl deposition of metals, an electrolyte conduit,'an.ano'de at the ingress of .the conduit,-

and a cathode at thelegress-thereof, the'anode andcathode being locatedtvitbin the conduit and connected with a sourceofelectrical current supply.

` lyticld'eposition of metals, an electrolyte con-` 4. In a coupling forhsystemsforithe electroduit composed of electrical and nonelectrical .conductingjmaterials at thev ingress and egressthereof,.respectively, anga'node within the electrical conducting `portion of the conduit- Y at the "ingress thereof,`and an elongated cathode adjacent the bottom of the .non-elec' trical portion ,at the e ress of the conduit,

' a'source of electrical current supply.

5. In a lsystem for'theelectrolytic deposii tion of metals, a plurality of electrolytic cells,

ries to produce electrolysis therein, and an' interconnecting electrolytic cell toldi'rect the passageofanv electrolyte between the' first means electrically connecting the cells in sementioned cells and to control withinthe inv 'ence in potential .between said cells.

terconiiecting cell anyfelectrolytic deposition within the portion of theelectrolyte 'which passes between said cells'caused by a diier- In asystem for-the' electrolytic deposition'of 'meta'.ls, a 'plurality o electrolytic cells, a conducting .lining within each of the cells, means electrically connectingfthe cells y iii-series to produce electrolysistherein, connectin electro yte between the cells, an i-anode posi- A means to direct the passage of' an means from tioned within the connecting means and elec#` trically connected with the lining of one cell,

and a cathode positioned within the connect` `l ing means and connected with the lining. of .another cell, 'the anode and cathode serylng.

to control electrolytic deposition' in the por,` tion of the electrolyte within the connecting means.

7'. In 'a system for the electrolytic deposi-i j .tion of metal s,`a plurality of electrolytic cells,

a conductin lining for each of the cells, means electr1cally connecting the cells in seriesto produce electrolysisv therein, a conduit.-

to'direct the continuous flow of an electrolyte j from one cell to another, an an'fode within the conduit electrically connected with' the lining 'of one-of the4 cells, and a cathode within 'the conduit electrically connected with the lining ofthe other-cell".

8.-'Ina system for the electrolytic deposition of metals, a plurality of electrolytic cells, means electrically connecting the cells in seto perlnit'the flow o f'an electrolyte from V'one cell to another, an 'anode within the conduit at the ingressthereof, and a cathode within the conduit at the egressthereof, said`anode and vcatl'mdeserving to Aelect av localized metal demetal deposition within the interconnecting the electrolyteiiowing between the tanks.

10. In a system for the electrolytic deposition of metals, interconnected tanks for con- A taining an electrolyte, and means between the.

`tanks for regulating therebetween the electrories to produce electrolysis therein, a conduit lytic decomposition ofthe portion of the elec- I trolyte between the tanks.

1 1.' In a system or'the electrolytic deposi- 4 4 tion of metals, interconnected tanks for con- 'said anode andcathode eingY connected with l taining an electrolyte, and means for localizing between the tanks an electrolytic deposition from the portion of the electrolyte be.-4 tween the tanks.

12. vIn a system for the electrolyticdeposition ofgmetals, tanks for containing an electrolyte which circulates through the tanks,

and interconnecting means between the tanks for controlling the electrolytic deposition therein of the electrolyte vpassing therethrough.

In. witness whereof, I hereunto subscribe my .name this `8th day of December, A. D.

1926.` JAMES WALTER SCOTT. 

